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Objectives: Familial Adenomatous Polyposis (FAP) is an autosomal dominant predisposition to colon cancer. This hereditary genetic disease is characterized by more than 100 adenomatous polyps in colon and rectum. Additional features may include desmoids tumors, polyps in the upper gastrointestinal tract, osteomas and Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE). A mutation in APC (Adenomatous Polyposis Coli) is found in the majority of cases. Mutation detection and genetic analysis of APC in this syndrome is highly recommended as the penetrance is almost 100% by 40 years of age. The APC gene expanding on 5q21-q22 has 15 exons and has an ORF with 8538 nucleotides which codes a protein with 2843 amino acids. Materials and Methods: 5 families among 150 families were selected according to accepted diagnosis criteria of FAP. CSGE (Conformation Sensitive Gel Electrophoresis) technique for the first time was set up to screen mutations in all 15 exons of APC gene by this technique. Direct sequencing was used as gold standard to confirm CSGE results. Results: CSGE analysis showed electrophoresis migration anomalies and heteroduplex formation in exon 15 of APC in all patients. Further analysis by direct sequencing characterized these heteroduplexes as deleterious mutations. These mutations can be classified as non sense, frame shift and deletion. Conclusion: For the first time, CSGE technique was set up for mutation screening of coding and some parts of non coding regions of APC. In comparison with other screening methods, this technique has many advantages so it can be used in routine clinical laboratories. As mutation detection in APC is laborious, needs high tech technology and is expensive, finding sensitive and cost effective mutation screening technique would have direct positive effect on clinical management of families with familial susceptibility to colon cancer.

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 In order to reduce waste and increase the added value of marine products, this study utilized Caspian kutum fish scales as fish waste to extract gelatin. The effects of two methods—water-bath and ultrasound—on the physicochemical characteristics of the extracted gelatin were compared. Gelatin was extracted from Caspian kutum fish scales by water bath and ultrasound-assisted extraction at 60 °C for 1, 2, and 3 hours. The results showed that, in general, ultrasound caused a significant increase in the extraction yield, %protein, and %ash of the samples (P<0.05). The results of SDS-PAGE and FTIR analysis confirmed that ultrasound could affect the structure of gelatin proteins, and longer extraction times (2 and 3 hours) caused a decrease in the content of alpha chains compared to that of beta chains. The FTIR results showed amides A, B, I, II, III peaks, and these peaks became more intense in samples extracted by ultrasound and at higher extraction times. The melting point and gel strength of gelatin extracted by ultrasound were 26.67 °C and 269 g, respectively, which were significantly lower than those of the gelatin extracted by water bath (27.67°C and 307g, respectively) (P<0.05). The thermal analysis of gelatins showed that all samples had a broad endothermic peak between 35 °C and 200 °C related to water evaporation and an exothermic peak between 300 °C and 400 °C related to the thermal decomposition of gelatin.

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